This invention is related in general to telecommunications call processing and more particularly to a system and method of performing forced default routing of calls.
The network evolution as a result of the Telecommunication Act of 1996 has resulted in the need for specific procedures to support the ability of customers to change from one telecommunications service provider to another (hereafter referred to as Number Portability (NP)). Specific procedures and standards were developed by the telecommunications industry to support NP. The magnitude of these changes are significant and have created situations that can potentially stress network technology to the point of a catastrophic network event. Scenarios of financial management have also been created.
In most cases, a query is required for call delivery in an NP environment. The query consists of a Signaling System Number 7 (SS7) message sent from a query-originating switch to a network database to obtain the necessary routing information to route the call. The solution to achieve this is called the Location Routing Number (LRN) solution. When a customer places a call to a ported subscriber, the dialed number is sent in a query to the LRN application. The application returns the LRN which is then used by the querying switch and subsequent switches to route the call to the network element that has the same Network Routing Address (NRA) as the LRN. The querying switch places the called number into the Generic Address Parameter (GAP) of the IAM and marks the call as a queried call. This instructs downstream switching equipment that further querying is not necessary. It also provides the far-end switch with the appropriate dialed number information. Upon receipt at the far-end switch, the GAP and Called Party Address are reversed for service support and call completion.
The volume of queries to be performed in a network consists of wireless to wireline calls and calls that previously have not been dipped prior to arriving in the receiving network. This volume can be significant based on the number of non-queried calls delivered to the receiving network. Non-queried calls come from Competitive Local Exchange Carrier (CLECs) networks and Inter-exchange Carrier (IECs) networks that do not have the ability to perform queries or for some reason one or more of these networks did not perform the NP query (for example, a network outage of the NP Database). Of note, wireless networks were not scheduled to have query capabilities until Dec. 31, 1998 as indicated in the Telecommunications Act of 1996. As such, they will deliver traffic as normal to the incumbent wireline networks and expect the incumbent networks to perform the necessary NP query processing. The incumbent networks must have sufficient capacity engineered to handle this expanded need. The incumbent network is also allowed some form of cost recovery and management.
An incumbent network may be flooded with non-queried messages due to an event in an adjacent network. A failure in the adjacent network may cause all calls to be default routed to the incumbent network. This type of event could foreseeably drive the incumbent""s network equipment beyond its engineered capacity and as such the incumbent may lose its ability to effectively process calls. Therefore, it is desirable to process calls to avoid this congestion in the network.
From the foregoing, it may be appreciated by those skilled in the art that a need has arisen for an improved technique to handle calls in a number portability environment. In accordance with the present invention, a system and method of performing forced default routing of calls are provided that substantially eliminate or reduce disadvantages and problems associated with conventional number portability call processing techniques.
According to an embodiment of the present invention, there is provided a method of performing forced default routing of calls that includes receiving an initial address message associated with a call placed to a called party number. A forward call indicator bit is identified within the initial address message. A determination is made as to whether the forward call indicator bit is in a first state, the first state indicating that a local number portability query has not been performed for the initial address message. In response to determining that the forward call indicator bit was received in the first state, the forward call indicator bit is placed into a second state. The initial address message is transmitted for subsequent processing of the call based on the called party number without performing a local number portability query.
The present invention has various technical advantages over conventional number portability processing techniques. For example, one technical advantage is to force processing of a call based on the called party number without going through a database query. Another technical advantage of the present invention is to eliminate use of the Generic Address Parameter in the Initial Address Message. Yet another technical advantage is to provide query relief at tandem switches. Other technical advantages may be readily apparent to those skilled in the art from the following figures, description, and claims.